package com.atguigu.gulimall.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.atguigu.common.to.es.SkuEsModel;
import com.atguigu.common.utils.R;
import com.atguigu.gulimall.search.config.GulimallElasticSearchConfig;
import com.atguigu.gulimall.search.constant.EsConstant;
import com.atguigu.gulimall.search.feign.ProductFeignService;
import com.atguigu.gulimall.search.service.MallSearchService;
import com.atguigu.gulimall.search.vo.AttrResponseVo;
import com.atguigu.gulimall.search.vo.SearchParam;
import com.atguigu.gulimall.search.vo.SearchResult;
import lombok.extern.slf4j.Slf4j;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.NestedQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import javax.annotation.Resource;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @author: kaiyi
 * @create: 2020-09-03 01:21
 */
@Slf4j
@Service
public class MallSearchServiceImpl implements MallSearchService {

  @Autowired
  private RestHighLevelClient esRestClient;

  @Resource
  private ProductFeignService productFeignService;

  @Override
  public SearchResult search(SearchParam param) {

    //1、动态构建出查询需要的DSL语句
    SearchResult result = null;

    //1、准备检索请求
    SearchRequest searchRequest = buildSearchRequest(param);

    try{
      // 2、执行检索请求
      SearchResponse searchResponse = esRestClient.search(searchRequest, GulimallElasticSearchConfig.COMMON_OPTIONS);

      // 3、分析响应数据封装成我们需要的格式
      result = buildSearchResult(searchResponse, param);
      System.out.println(result);
    }catch (IOException e){
      e.printStackTrace();
    }

    return result;
  }


  /**
   * 构建结果数据
   * 模糊匹配，过滤（按照属性、分类、品牌，价格区间，库存），完成排序、分页、高亮,聚合分析功能
   * @param response
   * @return
   */
  private SearchResult buildSearchResult(SearchResponse response,SearchParam param) {

    SearchResult result = new SearchResult();

    //1、返回的所有查询到的商品
    SearchHits hits = response.getHits();
    List<SkuEsModel> esModels = new ArrayList<>();

    //遍历所有商品信息
    if (hits.getHits() != null && hits.getHits().length > 0) {
      for (SearchHit hit : hits.getHits()) {
        String sourceAsString = hit.getSourceAsString();
        SkuEsModel esModel = JSON.parseObject(sourceAsString, SkuEsModel.class);

        //判断是否按关键字检索，若是就显示高亮，否则不显示
        if (!StringUtils.isEmpty(param.getKeyword())) {
          //拿到高亮信息显示标题
          HighlightField skuTitle = hit.getHighlightFields().get("skuTitle");
          String skuTitleValue = skuTitle.getFragments()[0].string();
          esModel.setSkuTitle(skuTitleValue);
        }
        esModels.add(esModel);
      }
    }
    result.setProducts(esModels);

    //2、当前商品涉及到的所有属性信息
    List<SearchResult.AttrVo> attrVos = new ArrayList<>();
    //获取属性信息的聚合
    ParsedNested attrsAgg = response.getAggregations().get("attr_agg");
    ParsedLongTerms attrIdAgg = attrsAgg.getAggregations().get("attr_id_agg");
    for (Terms.Bucket bucket : attrIdAgg.getBuckets()) {

      SearchResult.AttrVo attrVo = new SearchResult.AttrVo();

      //1、得到属性的id
      long attrId = bucket.getKeyAsNumber().longValue();
      attrVo.setAttrId(attrId);

      //2、得到属性的名字
      ParsedStringTerms attrNameAgg = bucket.getAggregations().get("attr_name_agg");
      String attrName = attrNameAgg.getBuckets().get(0).getKeyAsString();
      attrVo.setAttrName(attrName);

      //3、得到属性的所有值
      ParsedStringTerms attrValueAgg = bucket.getAggregations().get("attr_value_agg");
      List<String> attrValues = attrValueAgg.getBuckets().stream().map(item -> item.getKeyAsString()).collect(
          Collectors.toList());
      attrVo.setAttrValue(attrValues);

      attrVos.add(attrVo);
    }

    result.setAttrs(attrVos);

    //3、当前商品涉及到的所有品牌信息
    List<SearchResult.BrandVo> brandVos = new ArrayList<>();
    //获取到品牌的聚合
    ParsedLongTerms brandAgg = response.getAggregations().get("brand_agg");
    for (Terms.Bucket bucket : brandAgg.getBuckets()) {
      SearchResult.BrandVo brandVo = new SearchResult.BrandVo();

      //1、得到品牌的id
      long brandId = bucket.getKeyAsNumber().longValue();
      brandVo.setBrandId(brandId);

      //2、得到品牌的名字
      ParsedStringTerms brandNameAgg = bucket.getAggregations().get("brand_name_agg");
      String brandName = brandNameAgg.getBuckets().get(0).getKeyAsString();
      brandVo.setBrandName(brandName);

      //3、得到品牌的图片
      ParsedStringTerms brandImgAgg = bucket.getAggregations().get("brand_img_agg");
      String brandImg = brandImgAgg.getBuckets().get(0).getKeyAsString();
      brandVo.setBrandImg(brandImg);

      brandVos.add(brandVo);
    }
    result.setBrands(brandVos);

    //4、当前商品涉及到的所有分类信息
    //获取到分类的聚合
    List<SearchResult.CatalogVo> catalogVos = new ArrayList<>();
    ParsedLongTerms catalogAgg = response.getAggregations().get("catalog_agg");
    for (Terms.Bucket bucket : catalogAgg.getBuckets()) {
      SearchResult.CatalogVo catalogVo = new SearchResult.CatalogVo();
      //得到分类id
      String keyAsString = bucket.getKeyAsString();
      catalogVo.setCatalogId(Long.parseLong(keyAsString));

      //得到分类名
      ParsedStringTerms catalogNameAgg = bucket.getAggregations().get("catalog_name_agg");
      String catalogName = catalogNameAgg.getBuckets().get(0).getKeyAsString();
      catalogVo.setCatalogName(catalogName);
      catalogVos.add(catalogVo);
    }

    result.setCatalogs(catalogVos);
    //===============以上可以从聚合信息中获取====================//
    //5、分页信息-页码
    result.setPageNum(param.getPageNum());
    //5、1分页信息、总记录数
    long total = hits.getTotalHits().value;
    result.setTotal(total);

    //5、2分页信息-总页码-计算
    int totalPages = (int)total % EsConstant.PRODUCT_PAGESIZE == 0 ?
        (int)total / EsConstant.PRODUCT_PAGESIZE : ((int)total / EsConstant.PRODUCT_PAGESIZE + 1);
    result.setTotalPages(totalPages);

    List<Integer> pageNavs = new ArrayList<>();
    for (int i = 1; i <= totalPages; i++) {
      pageNavs.add(i);
    }
    result.setPageNavs(pageNavs);


    //6、构建面包屑导航
    if (param.getAttrs() != null && param.getAttrs().size() > 0) {
      List<SearchResult.NavVo> collect = param.getAttrs().stream().map(attr -> {
        //1、分析每一个attrs传过来的参数值
        SearchResult.NavVo navVo = new SearchResult.NavVo();
        String[] s = attr.split("_");
        navVo.setNavValue(s[1]);
        R r = productFeignService.attrInfo(Long.parseLong(s[0]));
        if (r.getCode() == 0) {
          AttrResponseVo data = r.getData("attr", new TypeReference<AttrResponseVo>() {
          });
          navVo.setNavName(data.getAttrName());
        } else {
          navVo.setNavName(s[0]);
        }

        //2、取消了这个面包屑以后，我们要跳转到哪个地方，将请求的地址url里面的当前置空
        //拿到所有的查询条件，去掉当前
        String encode = null;
        try {
          encode = URLEncoder.encode(attr,"UTF-8");
          encode.replace("+","%20");  //浏览器对空格的编码和Java不一样，差异化处理
        } catch (UnsupportedEncodingException e) {
          e.printStackTrace();
        }
        //String replace = param.getQueryString().replace("&attrs=" + attr, "");
        //navVo.setLink("http://search.gulimall.com/list.html?" + replace);

        return navVo;
      }).collect(Collectors.toList());

      result.setNavs(collect);
    }


    return result;
  }


  /**
   * 准备检索请求
   * 模糊匹配，过滤（按照属性，分类，品牌，价格区间，库存），排序，分页，高亮，聚合分析
   * @return
   */
  private SearchRequest buildSearchRequest(SearchParam param) {

    SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();

    /**
     * 模糊匹配，过滤（按照属性，分类，品牌，价格区间，库存）
     */
    //1. 构建bool-query
    BoolQueryBuilder boolQueryBuilder=new BoolQueryBuilder();

    //1.1 bool-must
    if(!StringUtils.isEmpty(param.getKeyword())){
      boolQueryBuilder.must(QueryBuilders.matchQuery("skuTitle",param.getKeyword()));
    }

    //1.2 bool-fiter
    //1.2.1 catelogId
    if(null != param.getCatalog3Id()){
      boolQueryBuilder.filter(QueryBuilders.termQuery("catalogId",param.getCatalog3Id()));
    }

    //1.2.2 brandId
    if(null != param.getBrandId() && param.getBrandId().size() >0){
      boolQueryBuilder.filter(QueryBuilders.termsQuery("brandId",param.getBrandId()));
    }

    //1.2.3 attrs
    if(param.getAttrs() != null && param.getAttrs().size() > 0){

      param.getAttrs().forEach(item -> {
        //attrs=1_5寸:8寸&2_16G:8G
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();


        //attrs=1_5寸:8寸
        String[] s = item.split("_");
        String attrId=s[0];
        String[] attrValues = s[1].split(":");//这个属性检索用的值
        boolQuery.must(QueryBuilders.termQuery("attrs.attrId",attrId));
        boolQuery.must(QueryBuilders.termsQuery("attrs.attrValue",attrValues));

        NestedQueryBuilder nestedQueryBuilder = QueryBuilders.nestedQuery("attrs",boolQuery, ScoreMode.None);
        boolQueryBuilder.filter(nestedQueryBuilder);
      });

    }

    //1.2.4 hasStock
    if(null != param.getHasStock()){
      boolQueryBuilder.filter(QueryBuilders.termQuery("hasStock",param.getHasStock() == 1));
    }


    //1.2.5 skuPrice
    if(!StringUtils.isEmpty(param.getSkuPrice())){
      //skuPrice形式为：1_500或_500或500_
      RangeQueryBuilder rangeQueryBuilder = QueryBuilders.rangeQuery("skuPrice");
      String[] price = param.getSkuPrice().split("_");
      if(price.length==2){
        rangeQueryBuilder.gte(price[0]).lte(price[1]);
      }else if(price.length == 1){
        if(param.getSkuPrice().startsWith("_")){
          rangeQueryBuilder.lte(price[1]);
        }
        if(param.getSkuPrice().endsWith("_")){
          rangeQueryBuilder.gte(price[0]);
        }
      }
      boolQueryBuilder.filter(rangeQueryBuilder);
    }

    //封装所有的查询条件
    searchSourceBuilder.query(boolQueryBuilder);

    /**
     * 排序，分页，高亮
     */

    //排序
    //形式为sort=hotScore_asc/desc
    if(!StringUtils.isEmpty(param.getSort())){
      String sort = param.getSort();
      String[] sortFileds = sort.split("_");

      SortOrder sortOrder="asc".equalsIgnoreCase(sortFileds[1])?SortOrder.ASC:SortOrder.DESC;

      searchSourceBuilder.sort(sortFileds[0],sortOrder);
    }

    //分页
    searchSourceBuilder.from((param.getPageNum()-1)* EsConstant.PRODUCT_PAGESIZE);
    searchSourceBuilder.size(EsConstant.PRODUCT_PAGESIZE);

    //高亮
    if(!StringUtils.isEmpty(param.getKeyword())){

      HighlightBuilder highlightBuilder = new HighlightBuilder();
      highlightBuilder.field("skuTitle");
      highlightBuilder.preTags("<b style='color:red'>");
      highlightBuilder.postTags("</b>");

      searchSourceBuilder.highlighter(highlightBuilder);
    }



    /**
     * 聚合分析
     */
    //1. 按照品牌进行聚合
    TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg");
    brand_agg.field("brandId").size(50);


    //1.1 品牌的子聚合-品牌名聚合
    brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg")
        .field("brandName").size(1));
    //1.2 品牌的子聚合-品牌图片聚合
    brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg")
        .field("brandImg").size(1));

    searchSourceBuilder.aggregation(brand_agg);

    //2. 按照分类信息进行聚合
    TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg");
    catalog_agg.field("catalogId").size(20);

    catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));

    searchSourceBuilder.aggregation(catalog_agg);

    //2. 按照属性信息进行聚合
    NestedAggregationBuilder attr_agg = AggregationBuilders.nested("attr_agg", "attrs");
    //2.1 按照属性ID进行聚合
    TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId");
    attr_agg.subAggregation(attr_id_agg);
    //2.1.1 在每个属性ID下，按照属性名进行聚合
    attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
    //2.1.1 在每个属性ID下，按照属性值进行聚合
    attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attrs.attrValue").size(50));
    searchSourceBuilder.aggregation(attr_agg);

    log.debug("构建的DSL语句 {}",searchSourceBuilder.toString());

    SearchRequest searchRequest = new SearchRequest(new String[]{EsConstant.PRODUCT_INDEX},searchSourceBuilder);

    return searchRequest;
  }
}
